Arrangement having a coordinate measuring machine or microscope

ABSTRACT

A method includes generating image signals from which a two-dimensional image is generated. The method includes generating object image signals by capturing an examination object arranged in a space. The method includes generating overview image signals by capturing an overview of the space. The method includes receiving image information included in the generated object image signals and the generated overview image signals. The method includes combining a two-dimensional object image, generated from the object image signals, with a two-dimensional perspectively distorted overview image of the space, generated from the overview image signals, to form a two-dimensional output image. The method includes scaling the received image information with respect to an image size for forming the output image in a manner such that at least one dimension of the examination object captured both in the object image and in the overview image has a same size in the output image.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to German Application No. 20 2019 105838.2 filed Oct. 21, 2019. The entire disclosure of the applicationreferenced above is incorporated by reference.

FIELD

The present disclosure relates to examination devices and moreparticularly to coordinate measuring machines and microscopes.

SUMMARY

The innovation relates to an arrangement having an examination device.The examination device may be a coordinate measuring machine or amicroscope. The examination device has a capture device having a firstimage generating device and a second image generating device. The firstand the second image generating device are each designed to generateimage signals from which it is possible to generate a two-dimensionalimage. The first image generating device is positioned and designed suchthat it is possible for it to generate object image signals during theoperation of the measurement device by capturing an examination objectarranged in a space, that is to say a measurement object of thecoordinate measuring machine or an object that is to be examined by wayof the microscope. As used in the present application, the term“examination” includes “measurement.”

The second image generating device is positioned and designed such thatit is possible for it to generate overview image signals by capturing anoverview of the space, specifically before and/or during an examiningoperation—and in particular before, during and/or after the generationof the object image signals by the first image generating device. It ispossible for the second image generating device to use the same devicefor generating image signals as the first image generating device but tohave a different optical system that allows the recording of an overviewimage.

In a corresponding method for operating a coordinate measuring machineor microscope, the first and the second image generating device eachgenerate image signals from which a two-dimensional image is generated.The first image generating device generates the object image signals.The second image generating device generates the overview image signals.

Where this description refers to an object, this includes the case thatmore than one object and in particular at least one workpiece is/arelocated in the space and additionally that more than one object orworkpiece is captured by the first image generating device of themeasurement device.

The image signals are in particular the primary signals generated by theimage generating device from the capturing of the object. In the case ofa digital camera, these are for example the image values of the pixelsthat are generated by integrating the incident object radiation over theexposure time interval. In the case of a laser scanner, the primaryimage signals are for example the times of flight of the radiation orthe phase shifts of the measurement radiation, from which the distancefrom the reflection site on the surface of the examination object isascertained. In any case, the image signals contain image informationfrom which it is possible in particular to generate a two-dimensionalimage. Said image information can be processed further in particular bythe image generating device itself or by a device that is connected to asignal output of the image generating device. In that case, for example,corrections such as a distortion correction for correcting an opticalaberration can be performed, image information can be extracted orsuppressed for example by way of digital filters, and/or two-dimensionalimage information can be generated from three-dimensional imageinformation. The first image generating device can be an optical sensor.

Frequently, optical sensors for measuring a measurement object are usedon coordinate measuring machines. Optical sensors are also used ascomponents of microscopes. Optical sensors are understood to be sensorsthat receive electromagnetic radiation from the object. With respect tothe present innovation, in particular imaging optical sensors areconsidered, wherein the image may be a one-dimensional, two-dimensional,or three-dimensional image. One-dimensional images are generated forexample by sensors having a line matrix made up of sensor elements. Forexample, conventional digital cameras generate two-dimensional images.However, it is also possible for example that two-dimensional regions ofthe measurement object are scanned using point sensors orone-dimensional sensors and that two-dimensional images are generated inthis way. Three-dimensional images can be generated for example by TOF(time-of-flight) cameras. Another possibility in this respect isprovided by stereo camera systems or pattern projection systems. Theimage information that is generated can therefore be one-dimensional,two-dimensional, or three-dimensional, depending on the type of sensor.For example it is possible by combining the image information from aplurality of line scan cameras, by scanning the space using at least oneline scan camera, by accepting or processing an image from atwo-dimensional camera or by generating a projection image or sectionalimage from three-dimensional image information to generate atwo-dimensional object image that is used by embodiments of theinnovation. However, the innovation is not limited to the examples ofoptical sensors mentioned.

Furthermore, a space for arranging an object is provided, for example aworkpiece, which is captured by the optical sensor. Coordinate measuringmachines and microscopes frequently have at least one delimitation ofthe space, for example a fixed base or a movable plate for placement ofthe object. Optionally, in particular in the case of microscopes,additional holders may be provided for fixing the object in itsinstantaneous position.

It is advantageous in particular for planning, for manual control, andfor monitoring the measurement operation of a coordinate measuringmachine and the operation of microscopes if an object image of thecaptured object is represented together with an overview image. Theoverview image is an image of the space in which the object that is tobe captured can be positioned. In particular, a plurality of objectsthat are to be captured and further objects, which may be, for example,parts of and/or accessories belonging to the coordinate measuringmachine or the microscope, can be located in the space. Therefore, thecapture device has the second image generating device, which generatesthe overview image signals. The second image generating device can alsobe one of the aforementioned optical sensors. However, generating atelecentric image and thus a perspectively non-distorted image is morecomplicated in the case of an overview image than it is in the case of arelatively small capturing image of the object that is to be captured.

It is an object of the present innovation to specify an arrangementhaving a coordinate measuring machine or microscope of the typementioned in the introductory part, which make possible a simultaneousrepresentation of the object image and the overview image that isquickly capturable for an observer, with little outlay relating to thegeneration of the overview image. In particular, an adjustedrepresentation of the object image and of the overview image is to beautomatically prepared in the case of a position change of the regioncaptured by the first image generating device.

A corresponding problem forms the basis of a method for operating acoordinate measuring machine or microscope of the type mentioned in theintroductory part.

It is proposed to combine a two-dimensional object image, generated fromthe object image signals, with a two-dimensional perspectively distortedoverview image of the space, generated from the overview image signals,to form a two-dimensional output image. In particular, an imagerepresentation device can be provided on which the output image isrepresented so as to be visually recognizable for a user.

It is furthermore proposed that the image processing device scales thereceived image information with respect to an image size in a mannersuch that the object captured both in the object image and in theoverview image has the same size in the output image. Since the objectin the object image does not have to have been captured in its entirety,the “same size” does not refer to the entire object. Neither does thewording refer to the volume of the object or of the object part, butrather to its one-dimensional or two-dimensional appearance in theimages. In general terms, at least one dimension of an object capturedboth in the object image and in the overview image therefore has thesame size in the output image. In other words, the object image and theoverview image therefore have the same image scale, with respect to atleast one of the two image directions of the output image, at least inan image region in which part of the object is imaged. The image scaleis understood to mean the ratio of an imaged length to the length of animage unit (for example of a pixel) that images an object of the imagedlength. In the case of imaging that is not telecentric on the objectside, the image scale is dependent on the distance of the imaged regionfrom the image generating device.

The representation of the object or of the object part with the samesize in the output image overcomes the disadvantage of the perspectivedistortion of the overview image and allows the observer of the outputimage to easily capture simultaneously the image content of the overviewimage and of the object image. In particular, if the size were notadjusted, i.e. without scaling, the observer would have to perform sizeadjustment of the overview image for example mentally to correctly fitthe object image into the overview image. Such specific adaptation isadvantageous in particular during planning, control and monitoring of ameasurement or capturing operation.

In particular, the following is proposed: an arrangement having acoordinate measuring machine or microscope, wherein the coordinatemeasuring machine or the microscope has a capture device having a firstimage generating device and a second image generating device, whereinthe first and the second image generating device are each designed togenerate image signals from which it is possible to generate atwo-dimensional image, the first image generating device is positionedand designed such that it is possible for it to generate object imagesignals during the operation of the measurement device by capturing anexamination object arranged in a space, that is to say a measurementobject of the coordinate measuring machine or an object that is to beexamined by way of the microscope, the second image generating device ispositioned and designed such that it is possible for it to generateoverview image signals by capturing an overview of the space beforeand/or during the operation of the measurement device, the capturedevice is furthermore connected to an image processing device of thearrangement, which is connected to the first and the second imagegenerating device to receive generated image information relating to theobject and the space, the image processing device is designed to combinea two-dimensional object image, generated from the object image signals,with a two-dimensional perspectively distorted overview image of thespace, generated from the overview image signals, to form atwo-dimensional output image, and the image processing device isdesigned to scale the received image information with respect to animage size for forming the output image in a manner such that at leastone dimension of the examination object captured both in the objectimage and in the overview image has the same size in the output image.

In the case of a corresponding method for operating a coordinatemeasuring machine or microscope in which the coordinate measuringmachine or the microscope has a capture device having a first imagegenerating device and a second image generating device, the first andthe second image generating device each generate image signals fromwhich a two-dimensional image is generated. Furthermore the first imagegenerating device generates object image signals by capturing anexamination object arranged in a space, that is to say a measurementobject of the coordinate measuring machine or an object that is to beexamined by way of the microscope, the second image generating devicegenerates overview image signals by capturing an overview of the spacebefore, during and/or after the generation of the object image signalsby way of the first image generating device, an image processing device,which is connected to the first and the second image generating device,receives generated image information relating to the object and thespace, the image processing device combines a two-dimensional objectimage, generated from the object image signals, with a two-dimensionalperspectively distorted overview image of the space, generated from theoverview image signals, to form a two-dimensional output image, and theimage processing device scales the received image information withrespect to an image size for forming the output image in a manner suchthat at least one dimension of the examination object captured both inthe object image and in the overview image has the same size in theoutput image.

Configurations of the method are evident from the description ofconfigurations of the arrangement. The image processing device can bepart of the measurement device or be realized entirely or partially byway of a separate device.

The image processing device receives the image information relating tothe object and the space. The image information can be the originalimage signals of the respective image generating device or it can be thealready processed image information from the image signals. In any case,the image processing device is able to receive or generate thetwo-dimensional image and to perform the scaling. In particular, thescaling can already be performed during the generation of thetwo-dimensional object image and/or of the two-dimensional overviewimage. Alternatively thereto, it is possible for a two-dimensionalobject image and/or a two-dimensional overview image to already beavailable, and the generating device can perform the scaling thereafter.

The scaling, i.e. size adjustment of an image, can be performed withrespect to two linearly independent image directions, that is to say ina two-dimensional digital image having rows and columns of pixels, inparticular with respect to the directions of the rows and the columns.Scaling can be performed on the overview image, on the object image, oron both images so as to then combine the available images to form theoutput image. However, scaling may be performed only on the overviewimage if only the overview image is perspectively distorted. Forexample, this may be the case where the first image generating device istelecentric on the object side and therefore the imaging of the objectdoes not result in a perspective distortion.

For example, the object image can be discernible on the output imageagainst the background of the overview image. This can be achieved forexample by virtue of the object image being completely discernible inthe representation of the output image and of pixels of the object imagereplacing pixels of the overview image at the respective position of theoutput image. However, it is likewise possible for elements of theoverview image to also be discernible in the output image at positionsof the object image. For example, contours of the overview image mayshow through. This can be achieved for example by pixels at positions ofthe object image that correspond to the contours being darker or havinga specified color in the output image.

All the images that are used to generate the output image, and theoutput image itself, are in particular digital images that have beencombined in particular from a two-dimensional arrangement of pictureelements (pixels). It is known that each picture element is positionedat a position in a regular two-dimensional coordinate system of theimage and is represented, upon representation by way of an imagerepresentation device, at a corresponding position of the representationmedium (for example screen or projection surface). The term image isalso used when a corresponding data set is present. An image thereforedoes not generally require that it is, in fact, represented. On theother hand, however, a corresponding data set is always representable,for example on a screen.

The viewing directions of the first image generating device duringcapturing of the object and of the second image generating device duringcapturing of the space having the object extend parallel to one anotherwith respect to the space or even coincide. If the first and/or thesecond image generating device is an image generating device having arotationally symmetric optical system, the viewing direction is definedby the optical axis of the optical system. Therefore, if the opticalaxes of the first and second image generating devices coincide, theoptical axes therefore extend along the same straight line in the space.This is generally achieved by the overview image signals being generatedby the second image generating device at a different time point thanwhen the object image signals are generated by the first imagegenerating device. For example, first the overview image signals can begenerated, and then sets of object image signals can be generatedrepeatedly by the first image generating device, wherein each set ofobject image signals corresponds to one time point or one brief timeperiod of the capturing of the object and at least one object image isgenerated from each set. In particular, the viewing directions of theimage generating devices extend parallel or on the z-axis of athree-dimensional Cartesian coordinate system x-y-z of the space andconsequently perpendicular to the x-y-plane of the space.

Parallel or coinciding viewing directions can be obtained in particularby way of calibrating the two image generating devices with respect totheir orientations, for example by using a calibration object that isarranged in the space and captured at least once by each of the imagegenerating devices. During the calibration, the orientation of the imagegenerating device can be set and/or it is possible to ascertain how theimage signals generated by the respective image generating device and/orimages generated therefrom are corrected by way of calculation. In sucha correction, it is in particular also possible for a distortioncorrection to be ascertained, with the result that after a correspondingperformance of the distortion correction, the respectively availablecorrected image is distortion-free in terms of the achieved accuracy.With respect to the overview image, a distortion does not relate to theperspective distortion. After correction of the distortion, for example,it is, however, possible for a perspective distortion of the overviewimage to exist, in which the image scale linearly increases along theviewing direction as the distance from the second image generatingdevice increases. In this case, straight beams traveling through thespace parallel to the viewing direction are distorted in the imageinformation generated by the second image generating device into beamsthat converge in the manner of a pyramid.

In particular, the coordinate systems of the image information generatedby the two image generating devices can be correlated with one another.Therefore, it is possible to perform a transformation of the imageinformation of the first image generating device into the coordinatesystem of the image information of the second image generating device,or vice versa, or into a common, third coordinate system with respect totwo linearly independent spatial directions, which extend in particularperpendicularly to the viewing directions of both image generatingdevices. The transformation with respect to the third spatial directionis not necessary because, in accordance with the innovation, at leastthe overview image is perspectively distorted and in each case scalingand consequently a size adjustment in particular with respect todifferent positions in or along the viewing direction takes place. Inparticular, the position can be specified from planning data (forexample CAD data) of an object arranged in the space or by a user. Inthe mentioned case of a three-dimensional Cartesian coordinate systemx-y-z, the transformation can have been performed with respect to thecoordinates x and y, and the z-position can be ascertained for examplein accordance with a test plan from the planning data, i.e. data of thedesired shape of the object. If a real object is then measured, it ispossible according to the test feature to be determined such as forexample a thickness, a diameter or another dimension to ascertain thez-position of the corresponding surface or of the corresponding regionof the object. To this end, it is possible to establish in advance in amanner known per se the relationship of the coordinate system of theplanning data to the coordinate system of the space in which the objectis arranged, for example by recording a plurality of images of theobject, by determining form features of the object from the images, andby correlating said form features with the corresponding form featuresfrom the planning data.

The coordinate systems can be correlated with one another in particularby way of recording a calibration object from the same recordingposition or from recording positions with the same viewing direction.For example, the calibration object is recorded by both image generatingdevices in a manner such that a marked point of the calibrationobject—such as for example a circle center of a circular calibrationobject—is in each case located in the image center of the generatedimage information. If a movement of a movable holder of the measurementdevice is required for the same recording position or for recordingpositions with the same viewing direction, the movement or the distancetraveled can be ascertained by way of a movement measurement system. Itis possible to immediately ascertain therefrom the two-dimensionaltransformation vector that is required for a transformation of the imageinformation of the first image generating device into the coordinatesystem of the image information of the second image generating device,or vice versa, with respect to the two linearly independent spatialdirections in a plane perpendicular to the viewing direction.

In particular, the stated dimension of the object that has the same sizeafter the scaling in the object image and in the overview image for theformation of the output image is defined such that it is to bedetermined along at least one line or in one surface, wherein the lineor the surface extends perpendicularly to a viewing direction of thefirst image generating device during the capturing of the examinationobject arranged in the space. With respect to the stated case of thethree-dimensional Cartesian coordinate system x-y-z, the line or thesurface is therefore located for example in a plane that is thex-y-plane of the space or a plane that is parallel thereto.

In particular, the image generating device can be designed to positionimage information from the overview image in the output image such thata first local region of the overview image, in which part of thecaptured examination object or the entire captured examination object isimaged, and a second local region of the object image, in which the samepart of the captured examination object or the entire capturedexamination object is imaged in the same size as in the overview image,form the same local region in the output image. In particular, theorientation of the imaged part of the captured examination object or ofthe entire captured examination object is also the same in thecombination of the overview image and the object image in the outputimage. Upon representation of the output image, the examination objector the part thereof is therefore discernible in the correct position andin the same viewing direction. It should be noted that the overviewimage in many cases images a greater part of the examination object thanthe object image. If therefore the object image images only a part ofthe examination object, said imaged part is, however, in most cases alsoimaged by the overview image and the corresponding local regions areimaged in the output image in the correct position and with the sameorientation. The first local region of the overview image is hereuniquely defined in the output image because other regions of theoverview image adjoin it. However, image information of the first localregion of the overview image may not be contained or only be partiallycontained in the output image and, instead, only or primarily imageinformation of the second local region of the object image may becontained in the output image. In particular in this common localregion, the image information from the object image is typically theimage information that is of greater importance for the user.

The image scale of the first and of the second image generating devicecan be ascertained in each case in advance for a common plane in thespace, wherein the viewing directions of the two image generatingdevices extend perpendicular to said common plane. The image planes ofthe two-dimensional images generated by the image processing device thenlikewise extend perpendicular to the viewing directions. The viewingdirections at least of one of the image generating devices can extend inparticular along the optical axis. The common plane may be a plane of asurface on which the examination object is able to be placed, forexample a surface of a placement plate or of an object holder. It hasalready been mentioned above that said surface can be a base or a platethat constitutes a delimitation of the space in which the examinationobject is able to be arranged.

The image scale can be ascertained for example by way of positioning aflat calibration object, which has known dimensions in both directionstransversely to the viewing direction, on the common plane. At least oneimage of the calibration object is then generated with each of the imagegenerating devices and the relationship of the imaging of thecalibration object to the known dimensions is established. In the caseof the second image generating device, which captures the space in aperspectively distorted fashion, this type of determination of the imagescale can likewise be performed in at least one further plane thatextends parallel to the common plane. This also applies to the firstimage generating device if it is not telecentric on the object side. Ifthe image scale increases linearly as the distance from the respectiveimage generating device increases, for example taking into considerationa correction of the optical distortion, the linear dependence canalternatively or additionally be taken into account in thedetermination. In particular, there are image generating devices havingoptical systems that have a point at which all object beams intersect inparticular after the correction of the optical distortion. At thispoint, the image scale is therefore zero.

Furthermore, the calibration can also be used to ascertain at least onecommon point in the coordinate systems of the first and of the secondimage generating device. For example, it is possible to use herefor ineach case a uniquely ascertainable point of the captured calibrationobject.

During the scaling of the received image information with respect to theimage size, it is therefore possible for previously ascertained imagescales with respect to a distance of the examination object to be takeninto account. In other words, for each distance, an image scale thatapplies thereto should be used. In the case of imaging that istelecentric on the object side and for which, under certaincircumstances, initially a distortion correction has been performed, theimage scale is not dependent on the distance from an imaged object. Inparticular, the distance can be the distance of an image point of theexamination object from the image generating device. For example, in thecase of the optical system having a point at which all object beamsintersect, the zero point for the determination of the distance can belocated at said point of intersection. The distance can be determined inparticular in a manner such that, for an arbitrary point that is notlocated in the viewing direction, the distance of a plane that extendsperpendicular to the viewing direction is considered. However, it isalso possible either to ascertain in each case the distance for aplurality of image points of the examination object and for theindividual image scale to be taken into account for each point, or it ispossible for an average value of the distance to be ascertained and forthe image scale of the average distance to be taken into account. Theaverage value can be for example an arithmetic mean or a weighted mean.As mentioned above, the dimension of the examination object may havebeen captured both in the object image and in the overview image. Thedimension has the same size due to the scaling, extends along a line ora surface perpendicular to the viewing direction. The dimensionconsequently relates to an object region the points of which are alllocated at the same distance from the image generating device.

If the image information was scaled taking into account the image scaleswith respect to the image size such that the at least one dimension ofthe examination object captured both in the object image and in theoverview image (or part of said examination object) has the same size inthe output image, it is optionally additionally possible, on the basisof the ascertained relationship between the coordinate systems of thefirst and of the second image generating device, for the correspondenceof the first local region of the overview image and of the second localregion of the object image to be established in the output image. It ispossible here in particular to take account of the fact that theoverview image is perspectively distorted. If therefore the relationshipbetween the coordinate systems for example in relation to the statedcommon plane has been established, it is possible, taking into accountthe distance of the local region from said plane, to likewise ascertainthe relationship of the coordinate systems. This in turn makes itpossible to establish for local regions at any position thecorrespondence of the first local region of the overview image and ofthe second local region of the object image in the output image.

With respect to the aforementioned coordinate system x-y-z, it istherefore possible, in the case of the viewing direction extending inthe z-direction, for the image scale in dependence on the z-value to beknown and in particular to be ascertained in advance. The relationshipof the coordinate systems of the first and of the second imagegenerating device can be known, and can in particular have beenascertained in advance, with respect to the x-y-plane at a definedz-position. The z-position is in particular located in the common planeof the image generating devices for which the scale has been or isascertained.

In particular, the image processing device can be designed to scaledifferently after a relative movement of the first image generatingdevice and the space, generation of new object image signals by way of anew capturing of the object and/or capturing of another object in thespace, the receipt of image information corresponding to the new objectimage signals, and the receipt of movement information relating to therelative movement than before. In particular, it is possible, takinginto account the movement information, for a two-dimensional objectimage, which has been generated from the new object image signals, to becombined with a two-dimensional perspectively distorted overview imageof the space, which has been scaled differently in accordance with therelative position of the first image generating device and the space,said relative position having changed after the relative movement, toform a two-dimensional output image. In this case, scaling is effectedsuch that at least one dimension of the object captured both in theobject image and in the overview image has the same size in the outputimage. The movement information can be generated for example by amovement measurement system of the measurement device and be received bythe latter. Alternatively or additionally thereto, a user may input themovement information.

The arrangement can furthermore have an input device for inputting aselected image position in the overview image, wherein a movementcontroller of the measurement device is designed to control a movementof the first image generating device in a manner such that the firstimage generating device is moved to a capturing position from which itcaptures a partial region of the space imaged in the overview image andthereby generates object image signals. An object imaged at the selectedimage position is located here in the partial region, and the dimensionof the object captured both in the object image and in the overviewimage relates to an object region of the object that is located in saidpartial region. In this way, it is possible to automatically generate asuitable object image in dependence on the input, and the scaling isfurthermore automatically performed. The selection of the image positionand the input thereof can be automatic, for example while workingthrough a specified test plan. Alternatively or additionally thereto, auser may select and input the image position.

The method for operating a coordinate measuring machine can be definedby the following clauses.

-   1. A method for operating a coordinate measuring machine or    microscope, wherein the coordinate measuring machine or the    microscope has a capture device having a first image generating    device and a second image generating device, wherein the first and    the second image generating device each generate image signals from    which a two-dimensional image is generated, and wherein

the first image generating device generates object image signals bycapturing an examination object arranged in a space, that is to say ameasurement object of the coordinate measuring machine or an object thatis to be examined by way of the microscope,

the second image generating device generates overview image signals bycapturing an overview of the space before, during and/or after thegeneration of the object image signals by way of the first imagegenerating device,

an image processing device, which is connected to the first and thesecond image generating device, receives generated image informationrelating to the object and the space,

the image processing device combines a two-dimensional object image,generated from the object image signals, with a two-dimensionalperspectively distorted overview image of the space, generated from theoverview image signals, to form a two-dimensional output image, and

the image processing device scales the received image information withrespect to an image size for forming the output image in a manner suchthat at least one dimension of the examination object captured both inthe object image and in the overview image has the same size in theoutput image.

-   2. The method as per clause 1, wherein the image processing device    positions image information from the overview image in the output    image such that a first local region of the overview image, in which    part of the captured examination object or the entire captured    examination object is imaged, and a second local region of the    object image, in which the same part of the captured examination    object or the entire captured examination object is imaged in the    same size as in the overview image, form the same local region in    the output image.-   3. The method as per clause 1 or 2, wherein the dimension of the    object is defined such that it is to be determined along at least    one line or in one surface, wherein the line or the surface extends    perpendicularly to a viewing direction of the first image generating    device during the capturing of the examination object arranged in    the space.-   4. The method as per one of the clauses 1 to 3, wherein the image    processing device, after

a relative movement of the first image generating device and the space,

generation of new object image signals by way of a new capturing of theobject and/or capturing of another object in the space,

the receipt of image information corresponding to the new object imagesignals, and

the receipt of movement information relating to the relative movement,

combines, taking into account the movement information, atwo-dimensional object image, which has been generated from the newobject image signals, with a two-dimensional perspectively distortedoverview image of the space, which has been scaled differently inaccordance with the relative position of the first image generatingdevice and the space, said relative position having changed after therelative movement, to form a two-dimensional output image, with theresult that at least one dimension of the object captured both in theobject image and in the overview image has the same size in the outputimage.

-   5. The method as per one of the clauses 1 to 4, wherein a selected    image position in the overview image is received, wherein a movement    of the first image generating device is controlled such that the    first image generating device is moved to a capturing position from    which it captures a partial region of the space imaged in the    overview image and thereby generates object image signals, wherein    an object imaged at the selected image position is located in the    partial region, and wherein the dimension of the object captured    both in the object image and in the overview image relates to an    object region of the object that is located in said partial region.

BRIEF DESCRIPTION OF THE DRAWINGS

Exemplary embodiments of the invention will now be described withreference to the accompanying drawing. In the individual figures of thedrawing:

FIG. 1 shows a coordinate measuring machine having a movable workpiecesupport and a movable sensor,

FIG. 2 schematically shows a block diagram of an arrangement having acapture device, an image processing device, and an image representationdevice,

FIG. 3 shows an output image that would be produced from an object imageand an overview image without scaling,

FIG. 4 shows an output image having the same object image as in FIG. 3,but wherein the overview image has been scaled, with the result that adimension of the examination object captured both in the object imageand in the overview image has the same size in the output image, and

FIG. 5 shows an output image as in FIG. 4, but wherein the object imagehas been made to coincide with the corresponding local region of theoverview image.

DETAILED DESCRIPTION

FIG. 1 shows a coordinate measuring machine 10 in accordance with oneexemplary embodiment of the innovation. The coordinate measuring machine10 has a workpiece support 12, realized here in the form of atranslation stage, i.e. displaceable in the horizontal directions x andy of the Cartesian coordinate system x-y-z of the coordinate measuringmachine 10. Such translation stages are also referred to as x-y-stages.The workpiece support 12 serves for positioning a measurement object(not illustrated in FIG. 1), which can be measured by the coordinatemeasuring machine 10.

The workpiece support 12 in this case has an upper part 16, which ismovable along two guide rails 18 in a first direction, the x-direction.The guide rails 18 are arranged on a lower part 20 of the workpiecesupport 12, which lower part is movable along further guide rails (notdiscernible in FIG. 1) in a second spatial direction, the y-direction.

The reference numeral 22 denotes a column, along which a carriage 24 ismovable in a third spatial direction, the z-direction. The carriage 24carries an optical sensor 26 as a first image generating device forgenerating image signals of the measurement object. Said object imagesignals form the measurement information for the measurement of themeasurement object. In addition, the carriage 24 can carry a tactilesensor 28. Instead of the optical sensor 26 or the tactile sensor 28, anoverview camera can be mounted on the carriage 24, in particulartemporarily, as a second image generating device. The overview cameraprovides overview image signals, from which a two-dimensional overviewimage for measurement objects and for accessory parts (for example amagazine for interchangeable sensors) is generated, in particular isgenerated by the overview camera itself.

The present innovation, however, is not limited to such coordinatemeasuring machines and can likewise be used in a coordinate measuringmachine that has a different holding structure for the optical sensorwith different movement directions for moving the sensor than shown inFIG. 1. For example, the coordinate measuring machine can have, insteadof the holding structure with the translation stage 12 and the column22, a holding structure of bridge design, portal design, horizontal-armdesign or other designs including hexapods.

The reference numeral 30 in FIG. 1 denotes an evaluation and controlunit, which is arranged in the exemplary embodiment on the fixed column22. The evaluation and control unit 30 serves for moving therespectively used sensor 26, 28 or the overview camera into a desiredmeasurement position relative to a measurement object on the workpiecesupport 12.

In addition, the evaluation and control unit 30 is able to determinecoordinates of selected measurement points on the measurement object andsubsequently geometric properties of the measurement object. A processor32 of the evaluation and control unit 30, by which the object image canbe visualized together with the overview image by way of controlling ascreen, which is not illustrated in FIG. 1, is illustratedschematically.

The evaluation and control unit 30 can also be realized differently thanillustrated. For example, it can be divided over two separatecomponents, wherein in particular the evaluation unit can be realized asa computer separate from the coordinate measuring machine. Alternativelyor in addition thereto, it is possible to use, instead of a screen, adifferent image representation device, such as an image projector.

In all cases, including cases that have not been mentioned, the imageprocessing device, which combines the two-dimensional object image withthe two-dimensional perspectively distorted overview image of the space,can be part of the evaluation and control unit and/or be realized by adevice that is separate from the coordinate measuring machine, such as acomputer for example. For example, a processor of the evaluation andcontrol unit, in particular the aforementioned processor 32, or aprocessor of the separate computer can provide and perform, controlledby software, the function of the image processing device. Not only withreference to the exemplary embodiment that was described on the basis ofFIG. 1, the first image generating device, a further device, such as anevaluation and control unit of the coordinate measuring machine, or theimage processing device can generate the two-dimensional object imagefrom the object image signals of the first image generating device.

The movability of a microscope can be realized in the same way as in thecoordinate measuring machine illustrated in FIG. 1, that is to say theworkpiece or observation object can be supported by a support that ismovable in one direction or in two independent directions, and theoptical sensor can be movable in a direction that is independent inparticular linearly independent, of the movement direction or themovement directions of the support.

FIG. 2 shows, in the left-hand part of the figure, a capture device 40with a first image generating device 41 for generating object imagesignals and with a second image generating device 42 for generatingoverview image signals. The first image generating device 41 isconnected to a drive apparatus 44 via a drive mechanical system 43, withthe result that a movement of the first image generating device 41 isdrivable in particular in the viewing direction thereof (to the left inFIG. 2). As is indicated by an arrow extending toward the driveapparatus 44, the drive apparatus 44 can be controlled, for example bytransmitting a signal containing information relating to the position ofthe first image generating device 41 that is to be set. Unlike what isillustrated in FIG. 2, the drive apparatus or a further drive apparatuscan be designed to move, alternatively or in addition, the examinationobject (not illustrated in FIG. 2). In any case, a relative movementbetween the examination object and the first image generating device isbrought about by the drive apparatus or by the drive apparatuses duringtheir operation.

As is indicated by in each case a line proceeding from the imagegenerating devices 41, 42, the latter are connected to an imageprocessing device 45, in the exemplary embodiment specifically to apre-processing device 46 of the image processing device 45. An output ofthe pre-processing device 46 is connected to an input of a scalingdevice 47 of the image processing device 45. An output of the scalingdevice 47 is connected to an input of a positioning device 48 of theimage processing device 45. An output of the positioning device 48 is inturn connected to an image representation device 50, for example ascreen.

The capture device 40 illustrated in FIG. 2 can in particular be part ofa coordinate measuring machine, such as the coordinate measuring machineillustrated in FIG. 1, or part of a microscope. As has already beendescribed on the basis of FIG. 1, the image processing device 45 canalso be for example a part of a control and evaluation computer of thecoordinate measuring machine. Alternatively, it can be part of amicroscope or be provided separately from the coordinate measuringmachine or the microscope.

The function of the arrangement illustrated in FIG. 2 is as follows, forexample: before, during and/or after the generation of the object imagesignals of an examination object by way of the first image generatingdevice 41, the second image generating device 42 generates image signalsof the space in which the examination object is located. The generatedimage signals are transferred to the pre-processing device 46, which isa device that is optionally provided and can also be omitted. Thepre-processing device 46 corrects in the image information for examplethe optical distortion in each case of the first or second imagegenerating device. Consequently, corrected image information relating tothe examination object and corrected image information relating to thespace are available at the output of the pre-processing device 46, theformer in the form of a two-dimensional object image. Said imageinformation is transferred to the scaling device 47.

The scaling device 47 scales the received image information with respectto an image size such that at least one dimension of the examinationobject captured both in the object image and in the overview image hasthe same size in the output image. The output image is prepared by thescaling device. However, it is generated in the exemplary embodiment bythe positioning device 48. In particular, the scaling device 47 maymerely scale the image information of the overview image. This is thecase in particular if the first image generating device is an imagegenerating device that is telecentric on the object side. In theexemplary embodiment, the dimension can be for example the radius ordiameter of the circular upper surface 5 of the cylinder or thecurvature of the outer boundary 4 thereof.

The image information processed by the scaling device 47 is transferredto the positioning device 48, which positions image information from theoverview image in the output image such that a first local region of theoverview image, in which part of the captured examination object or theentire captured examination object is imaged, and a second local regionof the object image, in which the same part of the captured examinationobject or the entire captured examination object is imaged in the samesize as in the overview image, form the same local region in the outputimage.

The scaling performed by the scaling device 47 can be carried out forexample in the case of digital image information by way of allocating acorresponding image scale. The image scale both of the object image andof the overview image at the output of the scaling device 47 can inparticular be related to the dimensions of the output image to beproduced. Said image scale is thus defined differently than theaforementioned image scales that are related to real dimensions forexample of the examination object or of the space or of a calibrationobject that was arranged earlier in the space.

The positioning device 48 performs the positioning for example in thecase of digital image data such that in particular the object image isrepositioned with respect to a coordinate system of the output imagesuch that the local regions of the object image and of the overviewimage correspond to one another.

The output image generated by the positioning device 48 is output to theimage generating device 50 and represented thereby.

FIG. 2 furthermore indicates by way of an arrow extending to the scalingdevice 47 that information required for the scaling, i.e. informationrelating to the z-position in the space coordinate system x-y-z, is ableto be input. In particular, this required information can furthermorecontain information relating to the position of the examination objectin the space and/or information relating to the position of the part ofthe examination object in the space captured by the object image. Thisposition information can in this case still be related to a common planeof the coordinate systems of the two image generating devices 41, 42. Inthis case, the positioning device 48 ascertains the position in theplane with respect to which the scaling was performed as soon as it hasreceived the corresponding image information and also, in the exemplaryembodiment, the position information from the scaling device 47.

FIG. 3 shows an object image 1, which is arranged centrally in apossible output image 3. The object image 1 is two-dimensional, which isindicated by a rectangular external boundary of the object image 1. Theobject image 1 shows an outer boundary 4 of a circular surface 5, whichis indicated in FIG. 3 and the following figures in hatched fashion byway of three diagonal lines. The object image 1, however, shows onlypart of the outer boundary 4 of the circular surface 5.

Furthermore, FIG. 3 shows on the right of the output image 3 an image 2of a cylinder in a perspective distorted illustration. At the time pointthat the overview image signals were generated, the base of the cylinderwas located further away from the second image generating device thanthe upper surface of the cylinder imaged in the foreground. The base istherefore likewise illustrated in the shape of a circle like the uppersurface. However, due to the perspective distortion of the overviewimage, it is smaller than the upper surface and is covered by thecylinder shaft and the upper surface. The shaft is shown to betransparent for the sake of the discernibility of the base.

FIGS. 3 to 5 are simplified illustrations. The overview image generallyhas image components in addition to the examination object. In the caseof FIGS. 3 to 5, the mentioned cylinder is the examination object,wherein the object image images merely part of the upper surface of thecylinder.

In FIG. 3, the part of the upper surface of the cylinder captured by theobject image 1 is greater than the corresponding part of the uppersurface in the overview image. Accordingly, FIG. 4 shows the state afterthe scaling. The scaling was performed by magnifying the image 2 of thecylinder as compared to FIG. 3, such that the size of the upper surfacenow corresponds to the size in the object image 1. This means inparticular that the radius of curvature of the outer boundary of theupper surface of the cylinder matches in both images. Generally, duringscaling, it is possible that not only the examination object, but theentire overview image and/or the object image is scaled.

The output image 3 illustrated in FIG. 4 is also not yet the outputimage that is ultimately output for representation, because the positionof the region of the circular surface 5 of the cylinder that is imagedin the object image 1 does not yet correspond to the position of theimage 2 of the cylinder in the overview image. By way of a correspondingdisplacement of the object image 1, as is indicated in FIG. 5 by anarrow pointing to the right, the correspondence of the position isachieved. The outer boundary 4 of the upper surface 5 of the cylinderillustrated by the object image 1 now corresponds to a portion of theouter boundary that is imaged in the image 2 of the cylinder. The objectimage 1 in its earlier position according to FIG. 4 is illustrated bydashed lines in FIG. 5.

It becomes obvious in terms of the scaling with reference to theexemplary embodiment of FIG. 4 that a detail change of the overviewimage occurs when scaling only the overview image and also when scalingthe overview image and the object image, certainly if the size of theoutput image is fixed. Therefore, in the exemplary embodiment of FIG. 4,a smaller detail of the overview image is presented and the position ofthe image 2 of the cylinder is moved to the right with respect to FIG.3. Generally, the image detail becomes smaller in the case of a scalingof the overview image that constitutes a magnification of the imagecomponents of the overview image, and vice versa. In particularsituations, this can result in the output image no longer beingcompletely filled by the overview image. By contrast, the object imagein most cases images a region of the space that is so small that, in theoutput image, it covers or forms merely a small portion of the outputimage in simultaneous representation with the overview image. The phraseat least one of A, B, and C should be construed to mean a logical (A ORB OR C), using a non-exclusive logical OR, and should not be construedto mean “at least one of A, at least one of B, and at least one of C.”

LIST OF REFERENCE SIGNS

-   1 Object image-   3 Output image-   4 Outer boundary-   5 Circular surface-   10 Coordinate measuring machine-   12 Workpiece support-   16 Upper part-   18 Guide rails-   20 Lower part-   22 Column-   24 Carriage-   26 Optical sensor-   28 Tactile sensor-   30 Evaluation and control unit-   32 Processor-   40 Capture device-   41 First image generating device-   42 Second image generating device-   43 Drive mechanical system-   44 Drive apparatus-   45 Image processing device-   46 Pre-processing device-   47 Scaling device-   48 Positioning device-   50 Image generating device

What is claimed is:
 1. An examination device that is at least one of acoordinate measuring machine and a microscope, the examination devicecomprising: a capture device including a first image generating deviceand a second image generating device and an image processing deviceconnected to the first image generating device and the second imagegenerating device of the capture device, wherein: the first imagegenerating device and the second image generating device are eachconfigured to generate image signals, from which a two-dimensional imageis generatable, the first image generating device is positioned andconfigured to generate object image signals during operation of theexamination device by capturing an examination object arranged in aspace, the second image generating device is positioned and configuredto generate overview image signals by capturing an overview of the spacebefore and/or during the operation of the examination device, and theimage processing device is configured to: receive image informationincluded in the generated object image signals and the generatedoverview image signals, wherein the image information relates to theexamination object and the space, combine (i) a two-dimensional objectimage, generated from the object image signals, with (ii) atwo-dimensional perspectively distorted overview image of the space,generated from the overview image signals, to form a two-dimensionaloutput image, and scale the received image information with respect toan image size to form the output image in a manner such that at leastone dimension of the examination object captured both in the objectimage and in the overview image has a same size in the output image. 2.The examination device of claim 1, wherein the image processing deviceis configured to, after: a relative movement of the first imagegenerating device and the space, generation of new object image signalsby way of a new capturing of the examination object and/or capturing ofanother examination object in the space, receipt of image informationcorresponding to the new object image signals, and receipt of movementinformation relating to the relative movement, combine, taking intoaccount the movement information, a two-dimensional object image,generated from the new object image signals, with a two-dimensionalperspectively distorted overview image of the space, scaled differentlyin accordance with a relative position of the first image generatingdevice and the space, the relative position being a changed relativeposition after the relative movement, to form a new two-dimensionaloutput image, wherein at least one dimension of the examination objectcaptured both in the new object image and in a new overview image has asame size in the new two-dimensional output image.
 3. A systemcomprising: the examination device of claim 1 and an input device forinput of a selected image position in the overview image, wherein: theexamination object is located in a partial region of the space imaged inthe overview image, a movement controller of the examination device isconfigured to control a movement of the first image generating devicesuch that the first image generating device is moved to a capturingposition from which the first image generating device is configured tocapture the partial region of the space imaged in the overview image andthereby generate the object image signals, and the dimension of theexamination object captured both in the object image and in the overviewimage relates to an object region of the examination object that islocated in the partial region.
 4. The examination device of claim 1,wherein the image processing device is configured to position imageinformation from the overview image in the output image such that afirst local region of the overview image, in which part of the capturedexamination object or the entire captured examination object is imaged,and a second local region of the object image, in which the same part ofthe captured examination object or the entire captured examinationobject is imaged in the same size as in the overview image, form thesame local region in the output image.
 5. The examination device ofclaim 4, wherein the image processing device is configured to, after: arelative movement of the first image generating device and the space,generation of new object image signals by way of a new capturing of theexamination object and/or capturing of another examination object in thespace, receipt of image information corresponding to the new objectimage signals, and receipt of movement information relating to therelative movement, combine, taking into account the movementinformation, a two-dimensional object image, generated from the newobject image signals, with a two-dimensional perspectively distortedoverview image of the space, scaled differently in accordance with arelative position of the first image generating device and the space,the relative position being a changed relative position after therelative movement, to form a new two-dimensional output image, whereinat least one dimension of the examination object captured both in thenew object image and in a new overview image has a same size in the newtwo-dimensional output image.
 6. The examination device of claim 4,wherein: the dimension of the examination object is defined such that itis to be determined along at least one line or in one surface and the atleast one line or the one surface extends perpendicularly to a viewingdirection of the first image generating device during the capturing ofthe examination object arranged in the space.
 7. The examination deviceof claim 6, wherein the image processing device is configured to, after:a relative movement of the first image generating device and the space,generation of new object image signals by way of a new capturing of theexamination object and/or capturing of another examination object in thespace, receipt of image information corresponding to the new objectimage signals, and receipt of movement information relating to therelative movement, combine, taking into account the movementinformation, a two-dimensional object image, generated from the newobject image signals, with a two-dimensional perspectively distortedoverview image of the space, scaled differently in accordance with arelative position of the first image generating device and the space,the relative position being a changed relative position after therelative movement, to form a new two-dimensional output image, whereinat least one dimension of the examination object captured both in thenew object image and in a new overview image has a same size in the newtwo-dimensional output image.
 8. The examination device of claim 1,wherein: the dimension of the examination object is defined such that itis to be determined along at least one line or in one surface and the atleast one line or the one surface extends perpendicularly to a viewingdirection of the first image generating device during the capturing ofthe examination object arranged in the space.
 9. The examination deviceof claim 8, wherein the image processing device is configured to, after:a relative movement of the first image generating device and the space,generation of new object image signals by way of a new capturing of theexamination object and/or capturing of another examination object in thespace, receipt of image information corresponding to the new objectimage signals, and receipt of movement information relating to therelative movement, combine, taking into account the movementinformation, a two-dimensional object image, generated from the newobject image signals, with a two-dimensional perspectively distortedoverview image of the space, scaled differently in accordance with arelative position of the first image generating device and the space,the relative position being a changed relative position after therelative movement, to form a new two-dimensional output image, whereinat least one dimension of the examination object captured both in thenew object image and in a new overview image has a same size in the newtwo-dimensional output image.
 10. A method for operating an examinationdevice that is at least one of a coordinate measuring machine and amicroscope, wherein the examination device includes a capture deviceincluding a first image generating device and a second image generatingdevice, the method comprising: generating, by each of the first imagegenerating device and the second image generating device, image signalsfrom which a two-dimensional image is generated; generating, by thefirst image generating device, object image signals by capturing anexamination object arranged in a space; generating, by the second imagegenerating device, overview image signals by capturing an overview ofthe space at least one of before, during, and after the generation ofthe object image signals by way of the first image generating device;receiving, by an image processing device connected to the first andsecond image generating devices, image information included in thegenerated object image signals and the generated overview image signals,wherein the image information relates to the examination object and thespace; combining, by the image processing device, a two-dimensionalobject image, generated from the object image signals, with atwo-dimensional perspectively distorted overview image of the space,generated from the overview image signals, to form a two-dimensionaloutput image; and scaling, by the image processing device, the receivedimage information with respect to an image size to form the output imagein a manner such that at least one dimension of the examination objectcaptured both in the object image and in the overview image has a samesize in the output image.
 11. The method of claim 10, wherein: aselected image position in the overview image is received, theexamination object is located in a partial region of the space imaged inthe overview image, a movement of the first image generating device iscontrolled such that the first image generating device is moved to acapturing position from which the first image generating device capturesthe partial region of the space imaged in the overview image and therebygenerates the object image signals, and the dimension of the examinationobject captured both in the object image and in the overview imagerelates to an object region of the examination object that is located inthe partial region.
 12. The method of claim 10, further comprisingpositioning image information from the overview image in the outputimage such that a first local region of the overview image, in whichpart of the captured examination object or the entire capturedexamination object is imaged, and a second local region of the objectimage, in which the same part of the captured examination object or theentire captured examination object is imaged in the same size as in theoverview image, form the same local region in the output image.
 13. Themethod of claim 12, wherein: a selected image position in the overviewimage is received, the examination object is located in a partial regionof the space imaged in the overview image, a movement of the first imagegenerating device is controlled such that the first image generatingdevice is moved to a capturing position from which the first imagegenerating device captures the partial region of the space imaged in theoverview image and thereby generates the object image signals, and thedimension of the examination object captured both in the object imageand in the overview image relates to an object region of the examinationobject that is located in the partial region.
 14. The method of claim12, wherein: the dimension of the examination object is defined suchthat it is to be determined along at least one line or in one surfaceand the at least one line or the one surface extends perpendicularly toa viewing direction of the first image generating device during thecapturing of the examination object arranged in the space.
 15. Themethod of claim 14, further comprising: receiving a selected imageposition in the overview image, wherein: the examination object islocated in a partial region of the space imaged in the overview image, amovement of the first image generating device is controlled such thatthe first image generating device is moved to a capturing position fromwhich the first image generating device captures the partial region ofthe space imaged in the overview image and thereby generates the objectimage signals, and the dimension of the examination object captured bothin the object image and in the overview image relates to an objectregion of the examination object that is located in the partial region.16. The method of claim 10, wherein: the dimension of the examinationobject is defined such that it is to be determined along at least oneline or in one surface and the at least one line or the one surfaceextends perpendicularly to a viewing direction of the first imagegenerating device during the capturing of the examination objectarranged in the space.
 17. The method of claim 16, further comprising:receiving a selected image position in the overview image, wherein: theexamination object is located in a partial region of the space imaged inthe overview image, a movement of the first image generating device iscontrolled such that the first image generating device is moved to acapturing position from which the first image generating device capturesthe partial region of the space imaged in the overview image and therebygenerates the object image signals, and the dimension of the examinationobject captured both in the object image and in the overview imagerelates to an object region of the examination object that is located inthe partial region.
 18. The method of claim 10, further comprising,after: a relative movement of the first image generating device and thespace, generation of new object image signals by way of a new capturingof the examination object and/or capturing of another examination objectin the space, receipt of image information corresponding to the newobject image signals, and receipt of movement information relating tothe relative movement, combining, taking into account the movementinformation, a two-dimensional object image, generated from the newobject image signals, with a two-dimensional perspectively distortedoverview image of the space, scaled differently in accordance with arelative position of the first image generating device and the space,the relative position being a changed relative position after therelative movement, to form a new two-dimensional output image, whereinat least one dimension of the examination object captured both in thenew object image and in a new overview image has a same size in the newtwo-dimensional output image.
 19. The method of claim 18, wherein: aselected image position in the overview image is received, theexamination object is located in a partial region of the space imaged inthe overview image, a movement of the first image generating device iscontrolled such that the first image generating device is moved to acapturing position from which the first image generating device capturesthe partial region of the space imaged in the overview image and therebygenerates the object image signals, and the dimension of the examinationobject captured both in the object image and in the overview imagerelates to an object region of the examination object that is located inthe partial region.